Bone fusion device, apparatus and method

ABSTRACT

A bone fusion method, apparatus and device for insertion between bones that are to be fused together and/or in place of one or more of the bones, such as, for example, the vertebrae of a spinal column. The bone fusion device comprises one or more extendable plates having a central rib. The bone fusion device includes one or more support channels configured to receive an insertion instrument that is then secured to the bone fusion device via a coupling mechanism. As a result, the coupled device is able to be securely positioned between vertebrae using the insertion instrument with minimal risk of slippage.

RELATED APPLICATIONS

This application claims priority under 35 U.S.C. § 119(e) of U.S.Provisional Patent Application Ser. No. 61/521,682, filed Aug. 9, 2011,and entitled “BONE FUSION DEVICE, APPARATUS AND METHOD,” which is herebyincorporated by reference.

FIELD OF THE INVENTION

This invention relates generally to bone fusion devices. Morespecifically, the present invention relates to devices for fusingvertebrae of the spine or other bones.

BACKGROUND OF THE INVENTION

The spinal column is made up of vertebrae stacked on top of one another.Between the vertebrae are discs which are gel-like cushions that act asshock-absorbers and keep the spine flexible. Injury, disease, orexcessive pressure on the discs can cause degenerative disc disease orother disorders where the disc becomes thinner and allows the vertebraeto move closer together or become misaligned. Similarly, vertebrae areable to weaken due to impact or disease reducing their ability toproperly distribute forces on the spine. As a result, nerves may becomepinched, causing pain that radiates into other parts of the body, orinstability of the vertebrae may ensue.

One method for correcting disc and/or vertebrae-related disorders is toinsert a fusion cage as a replacement for and/or in between thevertebrae to act as a structural replacement for the deteriorated discand/or vertebrae. The fusion cage is typically a hollow metal deviceusually made of titanium. Once inserted, the fusion cage maintains theproper separation between the vertebrae to prevent nerves from beingpinched and provides structural stability to the spine. Also, the insideof the cage is filled with bone graft material which eventually fusespermanently with the adjacent vertebrae into a single unit. However, itis difficult to retain this bone graft material in the cage and in theproper positions to stimulate bone growth.

The use of fusion cages for fusion and stabilization of vertebrae in thespine is known in the prior art. U.S. Pat. No. 4,961,740 to Ray, et al.entitled, “V-Thread Fusion Cage and Method of Fusing a Bone Joint,”discloses a fusion cage with a threaded outer surface, where the crownof the thread is sharp and cuts into the bone. Perforations are providedin valleys between adjacent turns of the thread. The cage can be screwedinto a threaded bore provided in the bone structure at the surgical siteand then packed with bone chips which promote fusion.

U.S. Pat. No. 5,015,247 to Michelson entitled, “Threaded SpinalImplant,” discloses a fusion implant comprising a cylindrical memberhaving a series of threads on the exterior of the cylindrical member forengaging the vertebrae to maintain the implant in place and a pluralityof openings in the cylindrical surface.

U.S. Pat. No. 6,342,074 to Simpson entitled, “Anterior Lumbar UnderbodyFusion Implant and Method For Fusing Adjacent Vertebrae,” discloses aone-piece spinal fusion implant comprising a hollow body having anaccess passage for insertion of bone graft material into theintervertebral space after the implant has been affixed to adjacentvertebrae. The implant provides a pair of screw-receiving passages thatare oppositely inclined relative to a central plane. In one embodiment,the screw-receiving passages enable the head of an orthopaedic screw tobe retained entirely within the access passage.

U.S. Pat. No. 5,885,287 to Bagby entitled, “Self-tapping Interbody BoneImplant,” discloses a bone joining implant with a rigid, implantablebase body having an outer surface with at least one bone bed engagingportion configured for engaging between a pair of bone bodies to bejoined, wherein at least one spline is provided by the bone bed engagingportion, the spline being constructed and arranged to extend outwardlyof the body and having an undercut portion.

U.S. Pat. No. 6,582,467 to Teitelbaum et al. entitled, “ExpandableFusion Cage,” discloses an expandable fusion cage where the surfaces ofthe cage have multiple portions cut out of the metal to form sharpbarbs. As the cage is expanded, the sharp barbs protrude into thesubcortical bone of the vertebrae to secure the cage in place. The cageis filled with bone or bone matrix material.

U.S. Pat. No. 5,800,550 to Sertich entitled, “Interbody Fusion Cage,”discloses a prosthetic device which includes an inert generallyrectangularly shaped support body adapted to be seated on hard endplates of vertebrae. The support body has top and bottom faces. A firstpeg is movably mounted in a first aperture located in the support body,and the first aperture terminates at one of the top and bottom faces ofthe support body. Further, the first peg projects away from the one ofthe top and bottom faces and into an adjacent vertebra to secure thesupport body in place relative to the vertebra.

U.S. Pat. No. 6,436,140 to Liu et al. entitled, “Expandable InterbodyFusion Cage and Method for Insertion,” discloses an expandable hollowinterbody fusion device, wherein the body is divided into a number ofbranches connected to one another at a fixed end and separated at anexpandable end. The expandable cage may be inserted in its substantiallycylindrical form and may be expanded by movement of an expansion memberto establish lordosis of the spine. An expansion member interacts withthe interior surfaces of the device to maintain the cage in the expandedcondition and provide a large internal chamber for receiving bonein-growth material.

These patents all disclose fusion cage devices that can be insertedbetween vertebrae of the spine in an invasive surgical procedure. Suchan invasive surgical procedure requires a long recovery period.

SUMMARY OF THE INVENTION

The present application is directed to a bone fusion method, apparatusand device for insertion between bones that are to be fused togetherand/or in place of one or more of the bones, such as, for example, thevertebrae of a spinal column. The bone fusion device comprises one ormore extendable plates having a central rib. The bone fusion device isable to be inserted between or replace the vertebrae by using anminimally invasive procedure. The bone fusion device comprises one ormore support channels configured to receive an insertion instrument thatis then secured to the bone fusion device via a coupling mechanism. As aresult, the coupled device is able to be securely positioned betweenvertebrae using the insertion instrument with minimal risk of slippage.After the device has been positioned between the vertebrae, and thescrew is rotated by the control mechanism to deliver the bone graftmaterial and extend the plates. Two plates are extended upon rotating arotating means wherein extending blocks travel up the screw pushing outthe angled plates as the extending blocks approach the ends of the bonefusion device. The central rib of the plates provides increased supportagainst torsional forces creating more stable contact with the bones. Insome embodiments, a single plate is extended. Thus, the plates are ableto be advantageously positioned in the confined space between thevertebrae to help brace the device until the bone has fused.

One aspect of the present application is directed to a bone fusionsystem for inserting a bone fusion device into a desired location. Thesystem comprises an insertion instrument comprising a coupling mechanismhaving a control mechanism and a plurality of fingers configured to movebetween a closed position wherein the fingers are close together to aspread position wherein the fingers are farther apart based onmanipulation of the control mechanism and a bone fusion device having abody and one or more extendable tabs, wherein the body of the bonefusion device is detachably coupled to the insertion instrument by thecoupling mechanism. In some embodiments, one or more of the fingerscomprise a fingertip that protrudes laterally from the finger. In someembodiments, the body comprises one or more surface channels configuredto receive the fingers and positioned along an exterior surface of thebody. In some embodiments, the body comprises a front end and aninterior cavity, and further wherein the channels are accessible fromthe front end and extend through the a plane perpendicular to the frontend. In some embodiments, each of the surface channels comprise agripping aperture for receiving the fingertip of the fingers of thegripping apparatus positioned within the surface channels. In someembodiments, the bone fusion device further comprises a positioningelement having a positioning aperture and positioned through the frontend and within the interior cavity of the body, and further wherein thepositioning element is mechanically coupled with the extendable tabssuch that moving the positioning element causes the extendable tabs tomove with respect to the body. In some embodiments, the surface channelsare positioned along the exterior surface on a plane perpendicular tothe positioning aperture of the positioning element such that thefingers of the gripping apparatus are able to enter the one or moresurface channels by moving parallel to the plane. In some embodiments,the insertion instrument further comprises a drive mechanism configuredto engage with and selectively rotate the positioning aperture when theinsertion instrument is coupled to the bone fusion device. In someembodiments, the control mechanism is coupled with the drive mechanismsuch that the drive mechanism is able to be rotated by manipulating thecontrol mechanism. In some embodiments, the insertion instrument isconfigured to prevent rotation of the drive mechanism if the fingers arenot in the closed position. In some embodiments, the insertioninstrument comprises a locking mechanism that when activated by atrigger prevents rotation of the drive mechanism until the lockingmechanism is deactivated by the trigger. In some embodiments, theinsertion instrument comprises an indicator that indicates datacorresponding to the amount of rotation of the drive mechanism. In someembodiments, the data indicated by the indicator indicates the currentposition of the tabs relative to the body of the bone fusion device. Insome embodiments, the indicator is adjustable such that the indicatorwill indicate different data corresponding to the same amount ofrotation of the drive mechanism based on the bone fusion devicecurrently coupled to the insertion instrument.

Another aspect of the present application is directed to a method ofoperation of the bone fusion system. The method comprises spreadingfingers of an insertion instrument with a control mechanism of theinsertion instrument, sliding the fingers of the insertion instrumentinto one or more surface channels of a bone fusion device and insertinga drive mechanism of the insertion instrument into the positioningaperture of a positioning element of the bone fusion device, contractingthe fingers with the control mechanism such that fingertips of thefingers move into gripping apertures of the surface channels and theinsertion instrument is detachably coupled with the bone fusion deviceand positioning the bone fusion device into a desired position with theinsertion instrument. In some embodiments, the method further comprisesextending one or more extendable tabs of the bone fusion device bymanipulating the control mechanism of the insertion instrument, whereinthe control mechanism is mechanically coupled with the drive mechanism.In some embodiments, the method further comprises spreading the fingerswith the control mechanism such that the fingertips of the fingers moveout of the gripping apertures of the surface channels and sliding thefingers out of the surface channels of the bone fusion device andremoving the drive mechanism from within the positioning aperture. Insome embodiments, controlling the spreading the fingers comprisespulling or pushing the control mechanism in or out of a shaft of theinsertion instrument. In some embodiments, extending the extendable tabscomprises rotating the control mechanism with respect to the fingers ofthe insertion instrument. In some embodiments, the method furthercomprises displaying data corresponding to the amount of rotation of thedrive mechanism with an indicator on the insertion instrument. In someembodiments, the data indicated by the indicator indicates the currentposition of the tabs relative to the body of the bone fusion device. Insome embodiments, the indicator is adjustable such that the indicatorwill indicate different data corresponding to the same amount ofrotation of the drive mechanism based on the bone fusion devicecurrently coupled to the insertion instrument. In some embodiments, thesurface channels are configured to receive the fingers and positionedalong an exterior surface of the body. In some embodiments, the bodycomprises a front end and an interior cavity, and further wherein thesurface channels are accessible from the front end and extend throughthe a plane perpendicular to the front end. In some embodiments, thepositioning element is positioned through the front end and within theinterior cavity of the body, and further wherein the positioning elementis mechanically coupled with the extendable tabs such that moving thepositioning element causes the extendable tabs to move with respect tothe body. In some embodiments, the surface channels are positioned alongthe exterior surface of the body on a plane perpendicular to thepositioning aperture of the positioning element such that the fingers ofthe gripping apparatus are able to slide into the one or more surfacechannels by moving parallel to the plane. In some embodiments, theinsertion instrument is configured to prevent rotation of the drivemechanism if the fingers are not fully contracted. In some embodiments,the insertion instrument comprises a locking mechanism that whenactivated by a trigger prevents rotation of the drive mechanism untilthe locking mechanism is deactivated by the trigger.

Another aspect of the present application is directed to an insertioninstrument for inserting a bone fusion device into a desired location.The instrument comprises an elongated body and a coupling mechanismpartially housed by the body and having a control mechanism and aplurality of fingers, wherein the plurality of fingers are configured tomove between a closed position wherein the fingers are close together toa spread position, wherein the fingers are farther apart based onmanipulation of the control mechanism. In some embodiments, one or moreof the fingers comprise a fingertip that protrudes laterally from thefinger. In some embodiments, the instrument further comprises a drivemechanism mechanically coupled with the control mechanism and configuredto rotate with respect to the body. In some embodiments, the controlmechanism enables selective rotation of the drive mechanism. In someembodiments, the instrument further comprises a stopping mechanism thatis configured to prevent rotation of the drive mechanism if the fingersare not in the closed position. In some embodiments, the instrumentfurther comprises a locking mechanism that when activated by a triggerprevents rotation of the drive mechanism until the locking mechanism isdeactivated by the trigger. In some embodiments, the instrument furthercomprises an indicator that indicates data corresponding to the amountof rotation of the drive mechanism. In some embodiments, the dataindicated by the indicator indicates the current position of extendabletabs of a bone fusion device coupled to the insertion instrumentrelative to a body of the bone fusion device. In some embodiments, theindicator is adjustable such that the indicator will indicate differentdata corresponding to the same amount of rotation of the drive mechanismbased on the bone fusion device currently coupled to the insertioninstrument.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A illustrates a top perspective view of the bone fusion deviceaccording to some embodiments.

FIG. 1B illustrates a top cutout view of the bone fusion deviceaccording to some embodiments.

FIG. 2 illustrates a side perspective view of the bone fusion deviceaccording to some embodiments.

FIG. 3 illustrates a cross-sectional view of components of the bonefusion device according to some embodiments.

FIG. 4A illustrates a cross sectional view of the bone fusion devicewith the plates compacted according to some embodiments.

FIG. 4B illustrates a cross sectional view of the bone fusion devicewith the plates extended according to some embodiments.

FIG. 5 illustrates a profile view of a bone fusion device having asingle plate extension/retraction mechanism according to someembodiments.

FIG. 6 illustrates a perspective view of a bone fusion apparatusaccording to some embodiments.

FIG. 7 illustrates a perspective view of the insertion instrumentaccording to some embodiments.

FIG. 8A illustrates a detailed top view of the coupling mechanism withinthe cover according to some embodiments.

FIG. 8B illustrates a detailed top view of a different couplingmechanism within the cover according to some embodiments.

FIG. 9 illustrates a side view of a finger according to someembodiments.

FIG. 10 illustrates a method of operating a bone fusion apparatusaccording to some embodiments.

FIG. 11 illustrates a bone fusion device having a rachet mechanismaccording to some embodiments.

FIG. 12A illustrates a cross sectional view of a bone fusion devicehaving a lock mechanism according to some embodiments.

FIG. 12B illustrates a side view of a lock mechanism according to someembodiments FIG. 13A illustrates a side cross sectional view of a bonefusion device having an oblong locking mechanism according to someembodiments.

FIG. 13B illustrates a frontal view of a body of the bone fusion deviceand the oblong locking mechanism according to some embodiments.

FIG. 13C illustrates a frontal view of a bone fusion device having anoblong locking mechanism in the unlocked position according to someembodiments.

FIG. 13D illustrates a frontal view of a bone fusion device having anoblong locking mechanism in the locked position according to someembodiments.

FIG. 13E illustrates a frontal view of a bone fusion device having anoblong locking mechanism in the unlocked position according to someembodiments.

FIG. 13F illustrates a frontal view of a bone fusion device having anoblong locking mechanism in the locked position according to someembodiments.

DETAILED DESCRIPTION

In the following description, numerous details and alternatives are setforth for purpose of explanation. However, one of ordinary skill in theart will realize that the invention can be practiced without the use ofthese specific details. For instance, the figures and description belowoften refer to the vertebral bones of a spinal column. However, one ofordinary skill in the art will recognize that some embodiments of theinvention are practiced for the fusion of other bones, including brokenbones and/or joints. In other instances, well-known structures anddevices are shown in block diagram form in order not to obscure thedescription of the invention with unnecessary detail.

FIGS. 1A and 1B illustrate a top perspective and cutout view of the bonefusion device 100 according to some embodiments. As shown, the bonefusion device 100 has a substantially rectangular shape and has two endfaces. The bone fusion device 100 is able to be constructed from a highstrength biocompatible material, such as titanium, which has thestrength to withstand compressive and shear forces in the spine that aregenerated by a patient's body weight and daily movements. Alternatively,part of all of the bone fusion device 100 is able to be constructed fromone or more of the group consisting of high strength biocompatiblematerial or a polymer such as PEEK, PEKK, and other polymeric materialsknow to be biocompatible and having sufficient strength. In someembodiments, the materials used to construct the bone fusion deviceinclude using additives, such as carbon fibers for better performance ofthe materials under various circumstances. The base biocompatiblematerial is often textured or coated with a porous material conducive tothe growth of new bone cells on the bone fusion device 100. The bonefusion device 100 has several conduits or holes 120 (also see FIG. 2)which permit the bone graft material to be inserted into the device 100and to contact the vertebral bone before or after the device 100 hasbeen inserted between the vertebrae of the patient. The bone graftmaterial and the surface texturing of the device 100 encourage thegrowth and fusion of bone from the neighboring vertebrae. The fusion andhealing process will result in the bone fusion device 100 aiding in thebridging of the bone between the two adjacent vertebral bodies of thespine which eventually fuse together during the healing period.

As further illustrated in FIGS. 1A and 1B, plates 130 are located onopposing sides of the bone fusion device 100. The plates 130 are shapedso that their outer surface is substantially flush with the frame 114 ofthe bone fusion device 100 in a nonextended position. Internally, theplates 130 have a central rib 124 and an angled inner surface.Specifically, the central rib 124 is configured to provide further outersurface area and structural support to the plates 130. Further, eachplate 130 is shaped such that one or more angled surfaces 123 of theplate 130 for extending the plate 130 have end thicknesses that arelarger than their middle thicknesses such that the thickness of theangled surfaces 123 gradually increases while going from the middle tothe ends of the plate 130. A positioning means 108 within the frame 114of the bone fusion device 100 comprises a positioning aperture 134, afirst screw 102 and a second screw 104 coupled together (see FIGS. 4Aand 4B). The positioning aperture 134 is configured to receive adrive/engaging mechanism 808 of a tool 602 (see FIGS. 6 and 8) such thatthe tool 602 is able to rotate the positioning means 108. Thepositioning aperture 134 is able to comprise numerous shapes and sizesas are well known in the art. The first screw 102 is threaded oppositeof the second screw 104. For example, if the first screw 102 is leftthreaded, the second screw 104 is right threaded or vice versa.Furthermore, the first screw 102 is of a slightly different size thanthe second screw 104. The positioning means 108 is coupled to a firstextending block 110 and a second extending block 112, each having a pairof rib slots 126 configured to receive the central ribs 124 of theplates 130 (see FIG. 1B). Specifically, the rib slots 126 are sized suchthat they permit the central ribs 124 to slide into and out of the slots126 (depending on the position of the blocks 110, 112) such that whenpositioned within the slots 126, the blocks 110, 112 are able to supportthe plates 130 against torsional forces by holding and supporting thecentral ribs 124.

Further, the first extending block 110 is coupled to the first screw 102and the second extending block 112 is coupled to the second screw 104,and the first extending block 110 and the second extending block 112 arepositioned in the middle of the bone fusion device 100 in the compactposition. When the positioning means 108 is turned appropriately, theextending blocks 110 and 112 each travel outwardly on their respectivescrews 102 and 104. As the extending blocks 110 and 112 traveloutwardly, they push the plates 130 outward and the central ribs 124slide within the rib slots 126. In other words, the inner plate surface123 when in contact with the extending blocks 110, 112 act in such amanner so as to push the respective plates 130 apart. Specifically, theangled surfaces 111 of each extending block 110, 112 are able to be incontact with the plate surfaces 123 and the center rib surface 121 is incontact with the extending block slot surface 125. Thus, the plates 130will be fully extended when the extending blocks 110 and 112 reach theopposite ends of the screws 102, 104. To retract the plates 130, thepositioning device 108 is turned in the opposite direction and theextending blocks 110 and 112 will each travel back to the middle ontheir respective screws 102 and 104 with the central ribs 124 within therib slots 126. When the extending blocks 110 and 112 are positioned inthe middle of the bone fusion device 100, the plates 130 are compact andare within the frame 114 of the bone fusion device 100. It iscontemplated that the operation of the device 100 is able to be reversedsuch that the plates 130, extending blocks 110, 112, and positioningmeans 108 are configured such that the extending blocks 110, 112 travelinwardly to extend the plates 130 into the extended position and traveloutwardly to retract the plates 130 into the compact position. In anycase, the nonextended plates 130 of the bone fusion device 100 provide acompact assembly that is suitable for insertion into the patient's bodythrough a open, or minimally invasive surgical procedure. As usedherein, an open or a minimally invasive procedure comprises a procedurewherein a smaller surgical incision is employed as compared to the sizeof the incision required for conventional invasive surgery, for examplearthroscopic procedures. Moreover, minimally invasive proceduresminimize or eliminate the need for excessive retraction of a patient'stissues such as muscles and nerves, thereby minimizing trauma and injuryto the muscles and nerves and further reducing the patient's recoverytime.

As the positioning means 108 is rotated causing the extending blocks 110and 112 to move closer to the ends of the respective screws 102 and 104,the extending blocks 110 and 112 push the plates 130 outward causing theplates 130 to assert pressure against surrounding bones and securing thebone fusion device 100 in place. When the extending blocks 110 and 112reach as close to the end of the positioning means 108 as allowed, theplates 130 are fully extended. Furthermore, since the extending blocks110 and 112 travel along the positioning means 108, along the threads ofthe screws 102 and 104, very precise positions of the plates 130 areable to be achieved. The plates 130 are able to have serrated edges orteeth 136 to further increase the bone fusion device's gripping abilityand therefore ability to be secured in place between the bones for botha long-term purchase and a short-term purchase. In some embodiments, theserrated edges or teeth 136 are able to be in a triangular or form atriangular wave formation as shown in FIG. 3. Alternatively, theserrated edges or teeth 136 are able to be filleted, chamfered, orcomprise other teeth shapes or edge waves as are well known in the art.

To secure the bone fusion device 100 in place, a user generally utilizesan insertion instrument such as a screw driver to turn the positioningmeans 108. Screw drivers unfortunately have the ability to slip out ofplace. When performing surgery near someone's spine, it is preferable toprevent or at least minimize the slipping ability. Further, it isnecessary to ensure that the surgeon is able to precisely place andcontrol the device via a robust connection to the device. To do so,channels 122 having gripping apertures 128 are implemented to receivegripping fingers 802 (see FIG. 8) coupled to a tool/insertion instrument602 (See FIG. 6) such that the tool 602 cannot slip out of place duringoperation. Specifically, the channels 122 are sized to receive thefingers 802 to prevent the tool 602 from moving laterally with respectto the head of the positioning means 108 and the gripping apertures 128are sized to receive the fingertips 904 (see FIG. 9) of the tool 602such that the fingers 802 (and tool 602) are unable to unintentionallybe pulled out of the channels 122 (and positioning means 108). In someembodiments, the channels 122 are offset such that when facing thepositioning aperture 134, one channel 122 is proximate the top left ofthe device 100 and the other channel 122 is proximate the bottom rightof the device 100. Alternatively, the channels 122 are able topositioned on other portions of the frame 114. In operation, asdescribed below in relation to FIGS. 6-10, a surgeon causes the fingers802 of the tool 602 to spread as they are inserted into the channels 122and then the surgeon causes the fingers 802 to clamp together insertingthe fingertips 904 into the gripping apertures 128 and fully securingthe tool 602 onto the device 100. Thus, the tool 602 is unable to slipout of place and is only able to be removed upon the spreading of thefingers 802 such that the fingertips 904 are removed from the apertures128 and the fingers 802 are removed from the channels 122. Furthermore,if the device 100 is next to relatively immovable tissue (e.g. bone,ligament or tendon under load), then this device 100 will still be ableto disengage, whereas one that relies on clamping by bending two rodstogether will not work if one of the rods is restricted by therelatively immovable tissue.

FIG. 2 illustrates a side perspective view of the bone fusion device 100according to some embodiments. The bone fusion device 100 utilizes thepositioning means 108 comprising the first screw 102 and the secondscrew 104 to move the first extending block 110 and the second extendingblock 112 outwardly from the middle of the bone fusion device 100towards its ends. The positioning means 108 is held in place butpermitted to turn utilizing one or more first pins 116. The one or morefirst pins 116 are secured within a retaining groove 106 (FIG. 3) of thepositioning means 108. The extending blocks 110 and 112 force the plates130 to either extend or retract depending on where the extending blocks110 and 112 are positioned. As described above, the plates 130 are ableto have serrated edges or teeth 136 to further increase grippingability. The plates 130 are each coupled to the frame 114 of the bonefusion device 100 by one or more pin slots 132 (FIGS. 3 and 4A) and oneor more second pins 118 wherein the one or more second pins 118 fitwithin the one or more pin slots 132 and are able to travel along theinterior of the one or more pin slots 132. In some embodiments, eachplate 130 is secured with a single second pin 118 and pin slot 132.Alternatively, one or more of the plates 130 are able to have multiplesecond pins 118 and pin slots 132. In some embodiments, the multiple pinslots 132 are able to be positioned at the corners of the plates 130similar to the single pin slot 132 shown in FIG. 3. In some embodiments,the multiple pin slots 132 of plates 130 are symmetric such that anyplate 130 is able to be placed on the top or bottom of the bone fusiondevice 100. Alternatively, the pin slots 132 of the plates 130 are ableto be positioned anywhere on the plate 130 and/or be positionedasymmetrically. The holes/conduits 120 within the plates 130 allow thebone graft material to contact the vertebral bone after the device 100has been inserted between the vertebrae of the patient. A set ofholes/conduits 120 within the frame 114 also allow bone graft materialto be inserted within the bone fusion device 100 after the bone fusiondevice 100 has been placed. The channels 122 having gripping apertures128 implemented to receive a tool are shown as well. Alternatively, thegripping apertures 128 are able to be omitted.

FIG. 3 illustrates a cross-sectional view of components of the bonefusion device 100 according to some embodiments. As described above, thepositioning means 108 comprises a first screw 102 and a second screw 104wherein the first screw 102 is threaded differently than that of thesecond screw 104. Furthermore, the first screw 102 is of a slightlydifferent size than the second screw 104. For example, in someembodiments the first screw 102 is an 8-32 screw and the second screw isa 6-32 screw. A retaining groove 106 is utilized to secure thepositioning means 108 in place. In some embodiments, the retaininggroove 106 is positioned opposite the end of the positioning means 108having the positioning aperture 134. To ensure that the tool does notslip while turning the positioning means 108, the channels 122 havingfingertip gripping apertures 128 are utilized to secure the tool asdescribed above. Alternatively, the fingertip gripping apertures 128 areable to be omitted and the channels 122 are able to secure the tool asdescribed above. A first extending block 110 and a second extendingblock 112 are utilized with the positioning means 108 to extend andcompact one or more of plates 130. The first extending block 110 has aninternal opening and threading to fit around the first screw 102. Thesecond extending block 112 has an internal opening and threading to fitaround the second screw 104. The frame 114 of the bone fusion device 100contains a set of holes/conduits 120 within the frame 114 for allowingbone graft material to be inserted. Furthermore, one or more first pins116 secure the positioning means within the frame 114. One or moresecond pins 116 in conjunction with one or more pin slots 132 secure theplates 130 to the frame 114.

FIG. 4A illustrates a cross sectional view of the bone fusion device 100with the plates retracted according to some embodiments. When theextending blocks 110 and 112 are positioned in the middle of thepositioning means 108 with the first screw 102 and the second screw 104,the plates 130 are positioned within the frame 114 of the bone fusiondevice 100 with the central ribs 124 slid within the rib slots 126. Theretaining groove 106 holds the positioning means 108 in place with oneor more first pins 116. The plates 130 are coupled to the frame 114 ofthe bone fusion device 100 using the one or more slots 132 and the oneor more second pins 118 wherein the one or more second pins 118 fitwithin the one or more slots 132 and are able to travel/slide along theinterior of the one or more slots 132.

FIG. 4B illustrates a cross sectional view of the bone fusion device 100with the plates extended according to some embodiments. As shown in FIG.4A, the bone fusion device 100 is compressed/contracted when theextending blocks 110 and 112 are in the middle of the bone fusion device100. As a user turns the positioning means 108 via the positioningaperture 134, the extending blocks 110 and 112 gradually move outwardfrom the middle. If the user turns the positioning means 108 in theopposite direction, the extending blocks move back towards the middle.As the extending blocks 110 and 112 are moving outward, the central ribs124 slide out of the rib slots 126 and the extending blocks 110, 112push on the plates 130. The plates 130 extend because the extendingblocks 110 and 112 exert force against the angled plates 130 outwardlyas shown by the arrows 140. When the extending blocks 110 and 112 arepositioned near the ends of the bone fusion device 100, the plates 130extend beyond the frame 114 of the bone fusion device 100 and ultimatelysecure the bone fusion device 100 between two bones. With the plates 130coupled to the frame 114 of the bone fusion device 100 by the one ormore slots 132 and the one or more second pins 118, the plates 130 areable to extend beyond the frame 114 of the bone fusion device 100 as theone or more second pins 118 travel within the interior of the one ormore slots 132.

In operation, the bone fusion device 100 is initially configured in acompact position such that the extending blocks 110, 112 are located inthe middle of the bone fusion device 100 thereby allowing the plates 130to rest within the frame 114 of the bone fusion device 100. The compactbone fusion device 100 is then inserted into position within thepatient. The surgeon is able to then the expand the bone fusion device100 by rotating the positioning means 108 which moves the extendingblocks 110, 112 towards the opposing ends of the bone fusion device100—one near the head of the positioning means 108 and the other towardsthe tail of the positioning means. As the extending blocks 110, 112 moveaway from the middle, the plates 130 are pushed outwardly from thepressure of the extending blocks 110, 112 against the angled plates 130.Initially, the central ribs 124 of the plates 130 remain at leastpartially within the rib slots 126 of the extending blocks 110, 112 suchthat the blocks 110, 112 are able to resist torsional forces on theplates 130 and/or device 100. Gradually, the central ribs 124 slide outof the rib slots 126 as the extending blocks 110, 112 approach the endsof the positioning means 108. Alternatively, the central ribs 124 areable to be configured such that they remain at least partially withinthe rib slots 126 as the extending blocks 110, 112 approach the ends ofthe positioning means 108. Alternatively, the central ribs 124 and/orrib slots 126 are able to be configured such that the central ribs 124are fully within the rib slots 126, fully removed from the rib slots126, or somewhere in between at any point along the path of theextending blocks 110, 112 from the center of the device to the ends ofthe device. Eventually the extending blocks 110, 112 exert asatisfactory force between the extended plates 130 and the bones to befused. At that point the bone fusion device 100 is able to remain inplace. Thereafter, material for fusing the bones together is insertedthrough the holes and openings 120 within the bone fusion device 100.Alternatively, the insertion of the material for fusing the bonestogether is able to be omitted.

FIG. 5 illustrates a bone fusion device 500 having a single plateextension/retraction mechanism according to some embodiments. The bonefusion device 500 shown in FIG. 5 is substantially similar to the bonefusion device 100 except for the differences described herein. Inparticular, the bone fusion device 500 comprises a half frame 514, oneor more half extending blocks 510, 512, a plate 530 and positioningmeans 508. Similar to the bone fusion device 100, the half extendingblocks 510, 512 are coupled around the positioning means 508 such thatwhen the positioning means 508 are turned, the blocks 510, 512 moveoutwards causing the plate 530 to move to the extended position. Thehalf frame 514 comprises a plate aperture (see FIG. 1A) for receivingthe plate 530 and a solid floor 538 opposite the plate aperture. In someembodiments, the floor 538 is able to have one or more floorholes/conduits for receiving or distributing grafting material into andout of the device 500. In some embodiments, the device 500 is sized suchthat when the plate 530 is in the compact/retracted position thedistance between the top of the plate 530 and the floor 538 is less thanor equal to 5 mm, and when the plate 530 is in the extended position thedistance between the top of the plate 530 and the floor 538 is less thanor equal to 7 mm. Alternatively, the device 500 is sized such that whenthe plate 530 is in the compact/retracted position the distance betweenthe top of the plate 530 and the floor 538 is in the range of 5 mm to 13mm and when the plate 530 is in the extended position the distancebetween the top of the plate 530 and the floor 538 is in the range of 7mm to 22 mm. Alternatively, other sizes of the device 500 arecontemplated as are well known in the art. Thus, by including only asingle plate 530, the height of the device 500 is able to be minimized.As a result, the bone fusion device 500 enables surgeons to use smallerincisions as well as to fit the bone fusion device 500 into smallerplaces and increasing the versatility of the device 500. Additionally,it should be noted that the single plate extension/retraction mechanismdescribed in FIG. 5 is able to replace each of the dual or multipleplate extension/retraction mechanisms described herein wherein thedevices having dual plate extension/retraction mechanisms areessentially halved (except for the positioning means) such that only oneplate is remaining.

FIG. 6 illustrates a bone fusion apparatus 600 according to someembodiments. As shown in FIG. 6, the bone fusion apparatus 600 comprisesa bone fusion insertion instrument 602 detachably coupled to a bonefusion device 604 via a coupling mechanism 606. In some embodiments, thebone fusion device 604 is substantially similar to the bone fusiondevice 100 described in FIGS. 1-5. Alternatively, the bone fusion device604 is able to be other embodiments of bone fusion devices describedherein or other types of bone fusion devices as are well known in theart. In some embodiments, the other types of bone fusion devices areable to be formed by one or more of polymers, bone, synthetic bone,metal or other biocompatible materials as are well known in the art. Insome embodiments, the coupling mechanism 606 comprises a clampingmechanism. Alternatively, the coupling mechanism 606 is able to compriseany combination of a clamps, screws, locks, adhesives or otherattachment elements as are well known in the art. In some embodiments,the insertion instrument 602 is able to detachably couple to a pluralityof bone fusion devices 604 simultaneously such that the plurality ofdevices 604 are able to be simultaneously controlled (e.g.extension/contraction of the plates) by the single insertion instrument602.

FIG. 7 illustrates a perspective view of the insertion instrument 602according to some embodiments. As shown in FIG. 7, the insertioninstrument 602 comprises a head 702 including the coupling mechanism 606and a cover 710, a shaft 704 having a readout element 706, and a controlmechanism 708 coupled to the coupling mechanism 606 through the shaft704. The head 702 is sized such that the cross-section of the head issmaller than the cross section of the bone fusion device 604. The cover710 is selectively retractable in order to enable easier/more thoroughcleaning of the coupling mechanism 606 after use. Specifically, thecover 710 is able to be extended such that the cover 710 surrounds atleast a portion of the coupling mechanism 606 in order to protect thecoupling mechanism 606 (see FIG. 8) during operation, as well as beingretracted exposing the previously covered portion of the couplingmechanism 606 for cleaning. The shaft 704 comprises a hollow tube thatsheaths at least a portion of the control mechanism 708 and theconnection of the control mechanism 708 to the coupling mechanism 606.

The readout element 706 is coupled to the control mechanism 708 and/orcoupling mechanism 606 such that the readout element 706 is able totrack the rotation of the drive mechanism 808 (see FIG. 8) of thecoupling mechanism 606 in order to determine the current amount ofextension of the plates 130. In some embodiments, the readout element706 comprises a mechanical scale that mechanically tracks the rotationsof the drive mechanism 808 and/or control mechanism 708. Alternatively,the readout element 706 is able to comprise an electronic or other typeof scale capable of tracking the rotation of the drive mechanism 808and/or control mechanism 708. In some embodiments, the readout element706 comprises a replaceable and/or adjustable scale or othermeasurement/display device such that the scale is able to be adjustedand/or replaced by another scale based on the bone fusion device 604 tobe coupled to the insertion instrument 602. For example, the scale isable to be selected/adjusted based on the amount each turn of thepositioning element 108 of the bone fusion device 604 extends one ormore of the plates 130. Thus, the readout element 706 provides thebenefit of providing accurate readings of the extension amount ofvarious types of bone fusion devices 604 to the users.

The control mechanism 708 is configured to enable a user to remotelyattach/detach the coupling mechanism 606 to the bone fusion device 604as well as remotely rotate the positioning means 108 of the device 604by controlling the rotation of the drive mechanism 808. In someembodiments, the control mechanism 708 mechanically controls thecoupling mechanism 606. For example, a user is able to release thecoupling mechanism 606 from the bone fusion device 604 by pushing thecontrol mechanism 708 into the shaft 704 and is able to couple thecoupling mechanism 606 to the bone fusion device 604 by pulling out thecontrol mechanism 708 from the shaft 704. Further, as another example, auser is able to rotate the drive mechanism 808 by rotating the controlmechanism 708. Alternatively, the control mechanism 708 is able tocontrol the coupling mechanism 606 by any combination of mechanically,pneumatically, electronically and other manners of controlling as arewell known in the art. As a result, the control mechanism 708 providesthe benefit of enabling a user to remotely control the coupling to thedevice 604, extension/retraction of the plates, and/or releasing of thedevice 604.

FIG. 8A illustrates a detailed top view of the coupling mechanism 606within the cover 710 according to some embodiments. In some embodiments,the top view of the coupling mechanism 606 is substantially similar tothe bottom view such that the coupling mechanism 606 is substantiallysymmetric. As shown in FIG. 8A, the coupling mechanism 606 comprises oneor more fingers 802, one or more finger pins 804, one or more slidingpins 806, a drive mechanism 808 and a body 810. The drive mechanism 808is coupled through the body 810 to the control mechanism 708.Specifically, the body 810 holds the drive mechanism 808 in placerelative to the fingers 802, but enables the drive mechanism 808 torotate in order to drive the bone fusion device 604 when desired. Thefingers 802 are coupled to the body 810 with one or more finger pins 804such that the fingers 802 are able to rotate about the one or morefinger pins 804. In some embodiments, there is one finger pin 804 foreach finger 802. The body 810 comprises one or more walls 812 that limitthe rotation of the fingers 802 (based on the dimensions of the fingers802) about the finger pins 804 to a preselected range of angles whereinat the greatest angle the fingers 802 are in an expanded/spread positionand at the smallest angle the fingers 802 are in a closed position. Inthe spread position, the fingertips 904 (see FIG. 9) of the fingers 802are separated by a distance greater than the distance between thesurface of the gripping apertures 128 and/or the channels 122 having thegripping apertures 128. In the closed position, the fingertips 904 areseparated by a distance equal to or less than the distance between thesurface of the gripping apertures 128 and/or the channels 122 having thegripping apertures 128. Thus, when in the closed position, thefingertips 904 are able to enter the gripping apertures 128 and securethe coupling mechanism 606 to the bone fusion device 604, and when inthe spread position, the fingertips 904 are able to be removed from thegripping apertures 128 thereby releasing the coupling mechanism 606 fromthe device 604. Alternatively, the fingertips 904 are able to be omittedand the separations in the spread and closed positions are determined bythe distance between the fingers 802 (without fingertips 904).

The sliding pins 806 are coupled to the cover 710 and cause the fingers802 to switch between the spread and closed positions as the couplingmechanism 606 is moved out of and into the cover 710 by the controlmechanism 708 based on the dimensions of the fingers 802. Specifically,in some embodiments, the sliding pins 806 are positioned adjacent thefingers 802 in the plane of rotation such that when coupling mechanism606 is retracted into the cover 710 the sliding pins 806 press againstan upper portion of the fingers 802 causing them to rotate the fingers802 to the closed position. Similarly, in some embodiments, when thecoupling mechanism 606 is extended out of the cover 710, the slidingpins 806 press against a lower portion of the fingers 802 causing themto rotate the fingers 802 to the spread/open position. Alternatively,the lower and upper portion of the fingers 802 is able to be configuredsuch that the retraction into the cover 710 causes the fingers 802 toswitch to the spread position and the extension causes the fingers 802to switch to the closed position. In some embodiments, the couplingmechanism 606 is configured such that the drive mechanism 808 is unableto rotate or otherwise operate unless the fingers 802 are in the closedposition. Alternatively, the coupling mechanism 606 is able to comprisea drive mechanism lock (not shown) that enables the user to lock thedrive mechanism 808 such that it is unable to rotate or otherwiseoperate until unlocked. FIG. 9 illustrates a side view of a finger 802according to some embodiments. As shown in FIG. 9, the finger 802comprises a body 906, a fingertip 904 and a finger aperture 902. In someembodiments, the finger 802 comprises one or more additional fingertips904 and/or finger apertures 902. The finger aperture 902 is sized toreceive a finger pin 804 in order to couple the finger 802 to the body810 while enabling the finger 802 to rotate about the finger pin 804 asdescribed above. The fingertip 904 protrudes from the body 906 such thatthe fingertip 904 is able to enter a gripping aperture 128. In someembodiments, the fingertip 904 comprises a beveled edge in order tofacilitate the alignment and insertion of the fingertip 904 into thegripping aperture 128. As shown, the body 906 of the finger 802comprises one or more bends 908 that (along with the walls 812)determine the extent at which the finger 802 is able to rotate about thefinger pin 804. In some embodiments, each bend 908 corresponds to adesired position of the finger/fingertips 802, 904. Alternatively, thefinger 802 is able to be substantially straight wherein the sliding pins806 are able to move in order to change the angle of the fingers 802.Thus, the coupling mechanism 606 provides the advantage of enabling auser to easily control the position of the fingers 802 between an openand closed position, wherein the closed position secures the insertioninstrument 602 to the bone fusion device 604 to prevent accidentalslippage.

FIG. 8B illustrates a detailed top view of an alternative embodiment ofthe coupling mechanism 606 within the cover 710. The coupling mechanism606 shown in FIG. 8B is able to be substantially similar to the othercoupling mechanism except for the differences described herein.Specifically, as shown in FIG. 8B, the coupling mechanism 606 comprisesa body 810 having one or more fingers 802 that extend from the body 810,one or more outer sliding pins 806A and one or more inner sliding pins806B. The outer and inner sliding pins 806A, 806B are coupled to thecover 710 and cause the fingers 802 to switch between the spread andclosed positions based on the dimensions of the finger walls 807A, 807Bas the coupling mechanism 606 is moved out of and into the cover 710 bythe control mechanism 708. In particular, as the coupling mechanism 606is moved out of the cover 710, the inner sliding pins 806B slide betweenand press against the inner finger walls 807B causing the inner fingerwalls 807B and thus the fingers 802 to separate. Conversely, as thecoupling mechanism 606 is moved into the cover 710, the outer slidingpins 806A slide onto and press against the outer finger walls 807Acausing the outer finger wall 807A and thus the fingers 802 to cometogether or close. As a result, by selectively moving the couplingmechanism 606 with respect to the cover 710 a user is able toselectively open and close the fingers 802 as desired.

In some embodiments, the fingers 802 are able to be biased in the openposition such that as they move out of the cover 710 they spreadautomatically and the inner sliding pins 806B are able to be omitted.Alternatively, the fingers 802 are able to be biased in the closedposition such that as they move into the cover 710 they closeautomatically and the outer sliding pins 806A are able to be omitted. Insome embodiments, the coupling mechanism 606 is configured such that thedrive mechanism 808 is unable to rotate or otherwise operate unless thefingers 802 are in the closed position. Alternatively, the couplingmechanism 606 is able to comprise a drive mechanism lock (not shown)that enables the user to lock the drive mechanism 808 such that it isunable to rotate or otherwise operate until unlocked.

A method of operation of the bone fusion apparatus 600 according to someembodiments will now be discussed in conjunction with the flow chartshown in FIG. 10. In some embodiments, one or more of the steps are ableto be omitted. A user causes the fingers 802 to spread with the controlmechanism 708 at the step 1002. In some embodiments, the fingers 802 arespread by pulling back on the control mechanism 708. Alternatively, thefingers 802 are able to be spread with other physical manipulations ofthe control mechanism 708 as are well known in the art. In someembodiments, the manner in which the control mechanism 708 causesspreading/closing of the fingers 802 is automated. Alternatively, themanner in which the control mechanism 708 causes spreading/closing ofthe fingers 802 is manual. The user slides the fingers 802 into thechannels 122 of the bone fusion device 604 and the drive mechanism 808into the positioning aperture 134 at the step 1004. In some embodiments,the sliding of the fingers 802 into the channels 122 and the drivemechanism 808 into the positioning aperture 134 occurs concurrently orsimultaneously. The user causes the fingers 802 to close with thecontrol mechanism 708 such that the fingertips 904 slide into thegripping apertures 128 of the channels 122 thereby detachably couplingthe insertion instrument 602 to the bone fusion device 604 at the step1006. In some embodiments, the fingers 802 are closed by pushing in onthe control mechanism 708. Alternatively, the fingers 802 are able to bespread with other physical manipulations of the control mechanism 708 asare well known in the art. The user positions the bone fusion device 604to the desired position within the patient with the insertion instrument602 at the step 1008. In some embodiments, the desired positioncomprises replacing a spinal disc with the bone fusion device 604 inbetween two vertebrae. Alternatively, the desired position is able tocomprise replacing a degenerated vertebrae with the bone fusion device604 in between the two adjacent vertebrae and/or spinal discs.Alternatively, the insertion instrument 602 is able to be used toposition other types of spinal devices such as a dynamic device, atotal/partial artificial disc, a nucleus pulposus or other medicaldevices as are well known in the art. In some embodiments, the bonefusion device 604 is inserted anteriorly. Alternatively, the bone fusiondevice 604 is able to be inserted posteriorly, laterally ortransforaminaly.

The user causes the drive mechanism 808 to rotate the positioning means108 with the control mechanism 708 in order to extend the plates 130 asdesired at the step 1010. In some embodiments, the user rotates thedrive mechanism 808 in order to rotate the positioning means 108.Alternatively, the user is able to otherwise manipulate the controlmechanism 708 in order to rotate the drive mechanism 808. In someembodiments, the manner in which the control mechanism 708 causes therotation of the drive mechanism 808 is automated. Alternatively, themanner in which the control mechanism 708 causes the rotation of thedrive mechanism 808 is manual. In some embodiments, the readout 706displays and dynamically adjusts a measurement of the amount of thecurrent expansion of the plates 130 outside of the frame 114 as thecontrol mechanism 708 rotates the drive mechanism 808. In someembodiments, the readout or indicator 706 comprises an adjustable and/orremovable scale. In some embodiments, the scale is able to be attachedand/or adjusted based on the bone fusion device 604 such that thereadout 706 outputs accurate readings of the expansion amount of theplates 130. In some embodiments, the measurement of the amount ofcurrent expansion of the plates 130 outside of the frame 114 comprisesthe amount of rotations of the drive mechanism 808 in one or moredirections since the drive mechanism 808 was inserted into thepositioning aperture. The user spreads the fingers 802 with the controlmechanism 708 thereby removing the fingertips 904 from the grippingapertures 128 and slides the drive mechanism 808 out of the positioningaperture 134 and the fingers 802 out of the channels 122 at the step1012. The user then removes the insertion instrument 602 from thepatient leaving the bone fusion device 604 to fuse with the surroundingbone during the healing process at the step 1014. As a result, themethod of operating the bone fusion apparatus 600 enables the surgeon tosecurely position the bone fusion device 604 and extend the plates 130as needed with minimal possibility of the drive mechanism 808 slippingout of the positioning aperture 134. Specifically, by coupling thefingertips 904 within the gripping apertures 128 and the fingers 802within the channels 122, the insertion instrument 602 is prevented frombeing pulled, pushed or twisted away from the bone fusion device 604.Thus, the procedure is made both safer and more efficient.

FIG. 11 illustrates a bone fusion device 1100 having a rachet mechanismaccording to some embodiments. The bone fusion device 1100 shown in FIG.11 is able to be substantially similar to the other bone fusion devicesexcept for the differences described herein. In particular, the bonefusion device 1100 comprises a body 1102, a positioning means 1104 and arachet mechanism including a pawl 1106 and one or more gear teeth 1108on the perimeter of the positioning means 1104. As shown in FIG. 11, thepawl 1106 is positioned within a cavity 1110 of the body 1102 that isadjacent to the positioning means 1104 such that the arm of the pawl1106 is able to abut or be in communication with the one or more gearteeth 1108. As a result, the pawl 1106 is able to permit the positioningmeans 1104 to rotate in one direction while preventing the positioningmeans 1104 from rotating back in the opposite direction. Specifically,the size and/or angles of the gear teeth 1108 are able to be adjustedsuch that as the positioning means 1104 rotate in a first direction thepawl 1106 is able to slide over the gear teeth 1108 due to the angle ofthe pawl 1106 and/or the angle of a first side of the gear teeth 1108.Contrarily, if the positioning means 1104 starts to rotate in a secondor opposite direction the pawl 1106 is unable to slide over the gearteeth 1108 due to the angle of the pawl 1106 and/or the angle of asecond or opposite side of the gear teeth 1108 thereby stopping orpreventing the rotation of the positioning means in the second oropposite direction. As a result, the bone fusion device 1100 having arachet mechanism provides the benefit of ensuring that the tabs stay inplace when extended because the rachet mechanism prevents them fromretracting.

In some embodiments, the rachet mechanism comprises a release mechanism(not shown) that when activated separates or changes the dynamic of thepawl 1106 and the gear teeth 1108 such that the positioning means 1104is able to rotate in the second or opposite direction without beingstopped by the pawl 1106. Alternatively, the angle of the pawl 1106and/or gear teeth 1108 of the rachet mechanism are able to be configuredsuch that with a desired force F the positioning means 1104 is able tobe rotated in the second or opposite direction despite the presence ofthe pawl 1106. In particular, the desired force F is able to be greaterthan the maximum force that would occur on the tabs within a patientafter implantation such that the rotation in the second direction wouldonly occur if the surgeon needed to rotate the positioning means 1104 inthat direction. In some embodiments, the pawl 1106 comprises nitinol orstainless steel. Alternatively, the pawl 1106 is able to comprise othertypes of suitable materials as are well known in the art. In someembodiments, the first direction of rotation corresponds to thedirection required to extend the tabs of the device 1100 and the seconddirection corresponds to the direction required to retract the tabs ofthe device. Alternatively, the first direction is able to correspond tothe direction required to retract the tabs of the device 1100 and thesecond direction corresponds to the direction required to extend thetabs of the device.

FIG. 12A illustrates a cross sectional view of a bone fusion device 1200having a lock mechanism according to some embodiments. The bone fusiondevice 1200 shown in FIG. 12A is able to be substantially similar to theother bone fusion devices except for the differences described herein.In particular, the bone fusion device 1200 comprises a body 1202, apositioning means 1204 and a lock mechanism including a collar 1206 anda choke 1208. As shown in FIG. 12B, the collar 1206 has a thick end1205, a narrow end 1207 and a gap 1210 and the choke 1208 is configuredto fit around the narrow end 1207 of the collar 1206. As a result, ifthe choke 1208 is pushed or otherwise forced down on the collar 1206towards the thick end 1205, it causes the gap 1210 of the collar 1206 tocontract thereby continually reducing the circumference of the collar1206 as it moves until the gap 1210 is gone. Similarly, if the choke1208 is moved back toward the narrow end 1207 of the collar 1206, thegap 1210 is able to continually increase up to its original sizeincreasing the circumference of the collar 1206 as permitted by theinner circumference of the choke 1208. As shown in FIG. 12A, the lockmechanism 1206, 1208 is positioned around the end of the positioningmeans 1204 within an aperture at an end of the body 1202. As a result,when the choke 1208 causes the circumference of the collar 1206 toreduce, it causes the collar 1206 to provide a choking force on thepositioning means 1204 such that the positioning means 1204 are unableto rotate due to the friction between the collar 1206 and the surface ofthe positioning means 1204. As a result, the lock mechanism is able toprovide the benefit of enabling the positioning means and thus the tabsto be locked in place thereby reducing the risk of the tabs undesirablyretracting.

In some embodiments, the choke 1208 has threading 1212 that correspondsto threading of the body 1202 such that if the choke 1208 is rotated thethreading 1212 causes the choke 1208 to move further in or out of theaperture of the body 1202 and thereby move with respect to the collar1206 in order to lock or unlock the positioning means 1204 as describedabove. In such embodiments, the choke 1208 is able to have one or morecutouts 1214 for receiving a tool for rotating the choke 1208.Alternatively, the threading 1212 is able to act as “snap-fit” stops orridges/valleys that correspond to ridges/valleys of the body 1202 suchthat if the choke 1208 is pushed further into the aperture of the body1202 and toward the thick end 1205 of the collar 1206, the ridges of thethreading 1212 compress and then spring/snap into the valleys of thebody 1202 thereby preventing the choke 1208 from being forced back awayfrom end thick end 1205 of the collar 1206. In some embodiments, thethickness of the collar 1206 gradually changes from the narrow end 1207to the thick end 1205. Alternatively, the thickness of the collar 1206is able to change in one or more increments. For example, the thicknessis able to remain substantially constant until the next increment isreached.

FIGS. 13A-F illustrate a bone fusion device 1300 having an oblong lockmechanism according to some embodiments. The bone fusion device 1300shown in FIGS. 13A-F is able to be substantially similar to the otherbone fusion devices except for the differences described herein. Asshown in FIGS. 13A and 13B, which illustrate side cross sectional andfrontal views respectively, the bone fusion device 1300 comprises a body1302, positioning means 1304 within the body 1203 and an oblong lockingmember 1306 surrounding one end of the positioning means 1304 and havingone or more bumps 1316. The body 1302 comprises an aperture 1308 forreceiving the positioning means 1304 and the locking member 1306,wherein the aperture 1308 includes one or more notches 1312 that areable to selectively receive the one or more bumps 1316. In particular,as shown in FIG. 13B, the aperture 1308 is oblong such that it has ashort side 1310A and a long side 1310B that correspond to a short side1314A and long side 1314B of the oblong locking member 1306.

As a result, as shown in FIG. 13D, the oblong locking member 1306 isable to be rotated into a “locked” position where the short side 1314Aof the locking member 1306 is positioned within the long side 1310B ofthe aperture 1308 and the long side 1314B of the locking member 1306 ispositioned within the short side 1310A of the aperture 1308. In thislocked position, the positioning means 1304 will be unable to rotatefreely as pressure is applied to the positioning means 1304 by the longside 1314B of the locking member 1306 in the direction indicated by thearrow because the long side 1314B is under compression by the short side1310A of the aperture 1308. In particular, the force applied to thepositioning means 1304 by the locking member 1306 in the locked positionincreases the friction between the positioning means 1304 and thelocking member 1306 such that the positioning means 1304 is unable torotate. In contrast, as shown in FIG. 13C, the oblong locking member1306 is able to be rotated into an “unlocked” position where the shortside 1314A of the locking member 1306 is positioned within the shortside 1310A of the aperture 1308 and the long side 1314B of the lockingmember 1306 is positioned within the long side 1310B of the aperture1308. In this “unlocked” position, the positioning means 1304 will beable to rotate freely as little or no pressure is applied to thepositioning means 1304 by the locking member 1306 because the lockingmember 1306 is not under compression by the aperture 1308. As a result,the lock mechanism is able to provide the benefit of enabling thepositioning means and thus the tabs to be locked in place therebyreducing the risk of the tabs undesirably retracting.

In some embodiments, the oblong locking member 1306 comprises PEEK.Alternatively, the oblong locking member 1306 is able to comprise othertypes of biocompatible materials that are flexible such that they areable to be compressed and apply a stopping force to the positioningmeans 1304. In some embodiments, the notches 1312 and the bumps 1316 areconfigured such that one or more of the bumps 1316 slide into thenotches 1312 when the oblong locking member 1306 is in either the lockedor unlocked positions. In particular, in such embodiments the bumps 1316and notches 1312 are able to provide an indication that the lockingmember 1306 has been fully rotated in the locked or unlocked position aswell as preventing the oblong locking member 1306 from slipping out ofthe locked or unlocked position. In some embodiments, the oblong lockingmember 1306 comprising one or more apertures that facilitate therotation of the locking member 1306 by a tool or user.

FIGS. 13E and 13F illustrate an alternate embodiment of the bone fusiondevice 1300 having the oblong locking mechanism according to someembodiments. In particular, as shown in FIGS. 13E and 13F, the aperture1308 and the oblong locking member 1306 are ovular such that they eachhave a short dimension 1318A, 1320A and a long dimension 1318B, 1320B.As a result, when rotated into a “locked” position as shown in FIG. 13F,the positioning means 1304 is unable to rotate freely as pressure isapplied to the positioning means 1304 from both sides along the longdimension 1318B of the locking member 1306 in the direction indicated bythe arrows because the long dimension 1318B is under compression by theshort dimension 1320A of the aperture 1308. In contrast, as shown inFIG. 13E, the oblong locking member 1306 is able to be rotated into an“unlocked” position where the short dimension 1318A of the lockingmember 1306 is positioned within the short dimension 1320A of theaperture 1308 and the long dimension 1318B of the locking member 1306 ispositioned within the long dimension 1320B of the aperture 1308. Like inFIG. 13C, in this “unlocked” position the positioning means 1304 will beable to rotate freely as little or no pressure is applied to thepositioning means 1304 by the locking member 1306 because the lockingmember 1306 is not under compression by the aperture 1308. In someembodiments, the aperture 1308 comprises one or more notches 1312 thatare configured such that ends of the long dimension 1318B slide into thenotches 1312 when the oblong locking member 1306 is in the lockedpositions. In particular, in such embodiments the notches 1312 are ableto provide an indication that the locking member 1306 has been fullyrotated in the locked or unlocked position as well as preventing theoblong locking member 1306 from slipping out of the locked or unlockedposition. Alternatively, the oblong locking member 1306 is able tocomprise on or more bumps 1316 for sliding into the notches 1312 inaddition to or in lieu of the ends of the long dimension 1318B. As aresult, the lock mechanism is able to provide the benefit of enablingthe positioning means and thus the tabs to be locked in place therebyreducing the risk of the tabs undesirably retracting.

The embodiments of the lock mechanism described herein and illustratedin FIGS. 11-13 are examples of particular lock mechanisms. As will beapparent to those skilled in the art, other appropriate lock mechanismsare able to be utilized within the bone fusion device described herein,to keep the rotatable fastener from moving.

Thus, the bone fusion device, apparatus and method described herein hasnumerous advantages. Specifically, the fingers and fingertips coupled tothe channels having gripping apertures ensure the non-slippage of thedriving mechanism during the operation of the bone fusion apparatus.Further, the lock mechanism is able to provide the benefit of enablingthe positioning means and thus the tabs to be locked in place therebyreducing the risk of the tabs undesirably retracting. Moreover, thesmall size of the single plate embodiments enables the use of smallerincisions and a more compact design. Also, as mentioned above, themethod of use requires only a small incision and minimally invasivesurgical procedure advantageously promoting health and rapid recovery bythe patient. Indeed, bone growth occurs around the bone fusion deviceand particularly at the locations of the extended plates, such that thebone fusion device is further secured by the bone growth, which furtherpromotes a superior, robust bone fusion result.

The present invention has been described in terms of specificembodiments incorporating details to facilitate the understanding ofprinciples of construction and operation of the invention. Suchreference herein to specific embodiments and details thereof is notintended to limit the scope of the claims appended hereto. It will beapparent to those skilled in the art that modification may be made inthe embodiments chosen for illustration without departing from thespirit and scope of the invention. For example, it should be noted thatalthough the above bone fusion devices are described in reference to apair of extending blocks, a pair of screws, and wherein each plate isshaped such that the ends are larger than the middle, and the size ofthe plate gradually increases while going from the middle to the ends,the use of a single extending block in the above embodiments iscontemplated. Specifically, if using a single extending block, the aboveembodiments would operate the same except the positioning means wouldcomprise a single screw that when engaged would cause the singleextending block to move from one end of the screw to the other endthereby exerting a force against the plates such that they move into theextended position. In such embodiments, each plate is shaped such thatone end is larger than the opposite end, and the size of the plategradually increases going from the smaller end to the larger end.

1-37. (canceled)
 38. A bone fusion device comprising: one or moreextendable tabs; a fusion body having a top, a bottom opposite the top,a first side, a second side opposite the first side, a first end, asecond end opposite the first end, an interior cavity, a first surfacechannel positioned on the first side of the fusion body and a secondsurface channel positioned on the second side of the fusion body,wherein the one or more extendable tabs extend from the top and thebottom of the fusion body; and a positioning element positioned withinthe interior cavity of the body, wherein the positioning element isconfigured to selectively move the one or more extendable tabs between aretracted position and an extended position.
 39. The bone fusion deviceof claim 38, wherein the first surface channel and the second surfacechannel are accessible from the first end and extend through a planeperpendicular to the first end.
 40. The bone fusion device of claim 39,wherein each of the first surface channel and the second surface channelcomprise a gripping aperture positioned within the first surface channeland the second surface channel for receiving an insertion instrument.41. The bone fusion device of claim 40, further comprising one or moresliding blocks operably coupled with the positioning element and theextendable tabs.
 42. The bone fusion device of claim 41, whereinrotation of the positioning element causes the sliding blocks to slidealong the positioning element thereby pushing the one or more extendabletabs out of the fusion body or enabling the one or more extendable tabsto slide back into the body.
 43. The bone fusion device of claim 42,wherein the positioning element comprises a first threaded portionthreaded in a first direction and a second threaded portion threaded ina second direction, opposite from the first direction.
 44. A bone fusiondevice comprising: a fusion body having a top, a bottom opposite thetop, a first side, a second side opposite the first side, a first end, asecond end opposite the first end, an interior cavity, a first surfacechannel positioned on the first side of the fusion body and a secondsurface channel positioned on the second side of the fusion body; one ormore extendable tabs; and a positioning element positioned within theinterior cavity of the fusion body, wherein the positioning element isoperably coupled with the one or more extendable tabs such that rotationof the positioning element causes the one or more extendable tabs tomove between a retracted position and an extended position; and alocking mechanism positioned around a head of the positioning element,wherein when the locking mechanism is moved from a free position to alocked position the locking mechanism pushes against the head of thepositioning element thereby inhibiting rotation of the positioningelement.
 45. The bone fusion device of claim 44, wherein the lockingmechanism comprises a choke and a tapered collar having a narrow end anda broad end positioned around the head of the positioning element. 46.The bone fusion device of claim 45, wherein an inner surface of thechoke is smaller than the broad end of the tapered collar such thatsliding the choke onto the collar from the narrow end to the broad endsqueezes the tapered collar causing the tapered collar to squeeze thehead of the positioning element.
 47. The bone fusion device of claim 46,wherein the choke comprises a plurality of exterior ridges and an innersurface of the aperture of the front end of the fusion body has interiorridges that interlock with the exterior ridges as the choke slides ontothe tapered collar from the narrow end to the broad end.
 48. The bonefusion device of claim 47, wherein the tapered collar has a gap suchthat the tapered collar does not form a complete tube.
 49. The bonefusion device of claim 44, wherein the locking mechanism comprises alocking member having a hole positioned around the head of thepositioning element, wherein the hole is offset from a center of thelocking member.
 50. The bone fusion device of claim 49, wherein aperimeter of the locking member comprises a plurality of bumps and aninner surface of the aperture of the front end of the fusion body has aplurality of notches for receiving one or more of the plurality ofbumps.
 51. The bone fusion device of claim 50, wherein the positioningelement is offset from a middle of the aperture of the front end of thefusion body.
 52. The bone fusion device of claim 44, wherein the lockingmechanism comprises an oblong locking member having an elongateddimension, a shorter dimension perpendicular to the elongated dimension,and a hole positioned around the head of the positioning element. 53.The bone fusion device of claim 52, wherein the aperture of the frontend of the fusion body is oblong such that the aperture has a longerdimension and a short dimension.
 54. The bone fusion device of claim 53,wherein an inner surface of the aperture of the front end of the fusionbody has a plurality of notches for receiving one or more edges of theoblong locking member extending in the elongated dimension when theelongated dimension aligns with one or more of the plurality of notches.55. The bone fusion device of claim 54, wherein the head of thepositioning element comprises a plurality of gear teeth and the lockingmechanism comprises a pawl operatively coupled with the plurality ofgear teeth.
 56. A bone fusion device comprising: one or more extendabletabs; a fusion body having a top, a bottom opposite the top, a firstside, a second side opposite the first side, a first end, a second endopposite the first end, an interior cavity, a first surface channelpositioned on the first side of the fusion body and a second surfacechannel positioned on the second side of the fusion body, wherein theone or more extendable tabs extend from the top and the bottom of thefusion body; a positioning element positioned within the interior cavityof the body, wherein the positioning element is configured toselectively move the one or more extendable tabs between a retractedposition and an extended position; and a locking mechanism coupled tothe positioning element, wherein when the locking mechanism is movedfrom a free position to a locked position, the locking mechanisminhibits rotation of the positioning element.
 57. The bone fusion deviceof claim 56, wherein the locking mechanism comprises a choke and atapered collar having a narrow end and a broad end positioned around thehead of the positioning element.
 58. The bone fusion device of claim 57,wherein an inner surface of the choke is smaller than the broad end ofthe tapered collar such that sliding the choke onto the collar from thenarrow end to the broad end squeezes the tapered collar causing thetapered collar to squeeze the head of the positioning element.
 59. Thebone fusion device of claim 58, wherein the choke comprises a pluralityof exterior ridges and an inner surface of the aperture of the front endof the fusion body has interior ridges that interlock with the exteriorridges as the choke slides onto the tapered collar from the narrow endto the broad end.
 60. The bone fusion device of claim 59, wherein thetapered collar has a gap such that the tapered collar does not form acomplete tube.
 61. The bone fusion device of claim 56, wherein thelocking mechanism comprises a locking member having a hole positionedaround the head of the positioning element, wherein the hole is offsetfrom a center of the locking member.
 62. The bone fusion device of claim61, wherein a perimeter of the locking member comprises a plurality ofbumps and an inner surface of the aperture of the front end of thefusion body has a plurality of notches for receiving one or more of theplurality of bumps.
 63. The bone fusion device of claim 62, wherein thepositioning element is offset from a middle of the aperture of the frontend of the fusion body.
 64. The bone fusion device of claim 56, whereinthe locking mechanism comprises an oblong locking member having anelongated dimension, a shorter dimension perpendicular to the elongateddimension, and a hole positioned around the head of the positioningelement.
 65. The bone fusion device of claim 64, wherein the aperture ofthe front end of the fusion body is oblong such that the aperture has alonger dimension and a short dimension.
 66. The bone fusion device ofclaim 65, wherein an inner surface of the aperture of the front end ofthe fusion body has a plurality of notches for receiving one or moreedges of the oblong locking member extending in the elongated dimensionwhen the elongated dimension aligns with one or more of the plurality ofnotches.
 67. The bone fusion device of claim 66, wherein the head of thepositioning element comprises a plurality of gear teeth and the lockingmechanism comprises a pawl operatively coupled with the plurality ofgear teeth.